2 VIEWS & REVIEWS

Justifying angiotemin blockers in ~ bypei1emion

As there are already several major groups of effective drugs for treating essential hypertension, can the introduction of another class, such as angiotensin blockers, be justified, asks MJ Brown from the UK. According to Brown, the answer appears to be 'yes'.

Angiotensiil receptor blockers prevent angiotensin II from reaching its main receptor, and losartan potassium is the agent at the furthest stage of development (phase III clinical trials). Brown suggests 2 possible advantages that angiotensin blockers may have over ACE inhibitors. These are: • improved tolerance, especially with respect to

patients who experience ACE inhibitor-induced cough. As the cough is most likely due to potentiation of a substrate of ACE, such as bradykinin, it should not be a side-effect of angiotensin receptor blockade.

• combination with ACE inhibitors whose efficacy may be attenuated by either breakthrough production of, or 'denervation-type' hypersensitivity to, angiotensin II. In the near future, the heterogeneity of essential

hypertension is likely to be confirmed by genetic studies, and Brown feels that the availability of more antihypertensive agents will help this process. When the genetic basis of essential hypertension is uncovered, it may be possible to identify which patients will benefit most from antihypertensives which cost many times more than thiazide diuretics. Brown MJ. Angiotensin receptor blacken in essential hypertension. Lancet 342: 1374-1375.4 Dec 1993 """7761

11 Dec 1993INPHARMAe ISSN 0156·2703l931121HlO2l$1.orf' Adlelntematlonel Ltd